Such automobile steering device is disclosed in Japanese Utility Model Unexamined Publication Sho 57-171964, particularly in FIG. 3 thereof.
According to said publication, the steering device comprises a steering shaft disposed in the front of the car interior and supported by the car body for rotation around its own axis extending rearwardly upward, steering wheel supported on the upper end of the steering shaft, a steering gear device disposed rearwardly of the lower end of said steering shaft, supported by said car body and operatively connected to right and left steering-purpose wheels, and an operative connection gear device disposed forwardly of said steering gear device and supported by the car body through a bracket and adapted to operatively connect said steering gear device to the lower end of said steering shaft.
Further, the operative connection gear device comprises a gear case constituting the outer shell thereof and supported by said bracket, an input gear housed in the gear case and operatively connected to the lower end of the steering shaft, and an output gear housed in the gear case and meshing with said input gear. Said steering gear device operatively is connected to the output gear by an universal joint shaft.
And when the driver positioned rearwardly of said steering wheel operates the steering wheel, the operating force is transmitted to the right and left steering-purpose wheels successively through said steering shaft, operative connection gear device input gear, output gear, universal joint shaft and steering gear device; thus, the automobile is steered in a desired direction.
In this connection, when primary collision of the automobile causes the front of the car body to move rearward with respect to the rear of the car body while it is plastically deformed successively from its front end to the rear, the operative connection gear device is pushed by the front of the rearwardly moving car body, so that it also moves rearward and sometimes pushes up the steering shaft rearwardly upward, in which case there is presented the possibility of said steering wheel approaching the driver.
And if the steering wheel approaches the driver as described above, the driver, upon primary collision, tends to come into secondary collision with the steering wheel from rearwardly above, which may produce a possibility that the shock to be applied to the driver upon secondary collision is unnecessarily great.
Further, in the prior art described above, the universal joint shaft is disposed to extend rearwardly downward. Therefore, when said operative connection gear device and said universal join shaft, pushed by the front of the car body, are successively rearwardly moved upon primary collision, as described above, the front side of the universal joint shaft tends to turn rearwardly upward substantially around the connecting section between the rear end of the universal joint shaft and the steering gear device.
And when the universal joint shaft turns rearwardly upward, as described above, the operative connection gear device connected to the front end of said universal joint shaft also turns rearwardly upward. Thereupon, the operative connection gear device pushes up the steering shaft rearwardly upward, as described above, to cause the steering wheel to approach the driver, which may produce a possibility that the shock to be applied to the driver upon secondary collision is unnecessarily great.
The present invention, which has been accomplished with the above in mind, is intended to solve the problem of mitigating the shock to be applied from the steering wheel to the driver upon secondary collision of the driver with the steering wheel from rearwardly above upon primary collision of the automobile.